Field of the Invention
The present invention relates generally to heat exchangers and heat transfer equipment, and in particular, to a heat exchanger arrangement that includes separately manufactured multiple fluid transfer components housed in a common unit with a common and integral header portion.
Description of the Related Art
In the field of vehicle construction, multiple heat exchangers are used to cool multiple and different fluid streams and flows. Each of these heat exchangers is customized with respect to joining techniques of the exchanger components and the arrangement of the tubes within the tube core in order to optimize the functioning of the exchanger according to the parameters needed for a particular type of cooling system. According to the prior art, distinct and separate heat exchanger units are used to accomplish the cooling requirements. Further, these separate and distinct units are connected through some physical attachment to each other, or to the vehicle frame. For example, in a transit bus application, a radiator, oil cooler and charge air cooler may be attached in a stacked and side-by-side arrangement. Such an arrangement allows the air stream, which is pulled by a fan, to contact each heat exchanger separately.
These multiple-unit (heat exchanger) systems allow for the units to be attached in a variety of manners. For example, the units can be stacked and attached by a welding process, a bolting arrangement, a brazing process or some other well-known attachment method. Still further, each unit includes a distinct tank and a distinct header.
U.S. Pat. No. 7,096,932 to Scoville et al. shows a multi-fluid heat exchanger having separate fluid flow paths for two separate fluid streams to be heated or cooled by a third fluid stream. Scoville et al. teach a heat exchanger comprising a pair of headers, a plurality of flattened tubes forming two groups of tubes extending between the headers, a pair of baffles in each header between the groups of tubes so as to maintain an atmospheric pressure between the groups of tubes and prevent a build up of gas pressure during brazing. Scoville et al teach that the heat exchanger is assembled and then placed within a brazing oven whereat the brazing compound at the various interfaces flow to bond and seal the interfaces of the various components.
U.S. Pat. No. 6,394,176 to Marsais also teaches a multi-fluid heat exchanger for cooling separate fluid streams comprising a pair of manifolds, a plurality of tubes extending between the manifolds forming two separate banks of tubes, and insulating partitions between the banks of tubes for insulating the two fluids from one another. Marsais stresses the need for standardization of tube size and manifold holes for ease of manufacture.
Other patents and publications that teach multi-fluid heat exchangers include U.S. Pat. Nos. 1,948,929; 2,037,845; 2,264,820; 2,505,790; 4,137,982; 4,651,816; 4,688,311; 4,923,001; 4,947,931; 5,009,262; 5,036,910; 5,129,144; 5,186,244; 5,186,246; 5,366,005; 5,720,341; 5,881,456; 6,035,927; 6,173,766; and 6,321,832 and U.S. Patent Application Publication 2002/0040776.